The Roselle Hibiscus Sabdariffa, more commonly known as sorrel, is a species of Hibiscus that is native to the tropics of the eastern hemisphere and is used for the production of bast fiber from the plant stem and the red calyces are used as an infusion for flavoring drinks. The plant is considered to have antihypertensive properties and has been used in folk medicine as a diuretic, mild laxative, and treatment for cardiac and nerve diseases and cancer. In addition to its well documented hypotensive effects, sorrel has one of the highest levels of antioxidants of any widely available food.
The fruit of the sorrel has red fleshy petals, called calyces, surrounding a large seed capsule in the center of the fruit. The red calyces of the plant are the primary object of the sorrel harvest and are increasingly exported to America and Europe. The present method of sorrel harvesting is largely a task of manual labor using a makeshift hand tool made from a tube having a serrated bottom and approximately the same diameter of the seed. The serrated end of the tube is used to cut through the base of the calyces and then push the seed capsule out of the fruit thereby leaving the calyces free.
This harvest methodology has two primary shortcomings. First, the labor cost is high since several laborers are required to pick the sorrel buds and remove the seeds from the calyces. Two laborers require approximately fifteen days to harvest one acre of sorrel. Secondly, as a result of the time period required for harvesting the preservation of the sorrel calyces is being compromised. The extensive time required for harvesting results in a significant delay before preservation and use, and thus the calyces start to break down and deteriorate. This is especially so when handling large quantities.
However, the current manual separation of the calyces petals from the seed capsules is a highly time consuming expenditure of manual labor. Therefore, an apparatus is needed to automate the separation process and reduce the time required to efficiently harvest the sorrel.